<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Filter
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Alnum.php 16870 2009-07-20 10:17:59Z mikaelkael $
 */

/**
 * @see Zend_Filter_Interface
 */
require_once 'Zend/Filter/Interface.php';
/**
 * @see Zend_Locale
 */
require_once 'Zend/Locale.php';

/**
 * @category   Zend
 * @package    Zend_Filter
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Filter_Alnum implements Zend_Filter_Interface
{
	/**
	 * Whether to allow white space characters; off by default
	 *
	 * @var boolean
	 * @deprecated
	 */
	public $allowWhiteSpace;

	/**
	 * Is PCRE is compiled with UTF-8 and Unicode support
	 *
	 * @var mixed
	 **/
	protected static $_unicodeEnabled;

	/**
	 * Locale in browser.
	 *
	 * @var Zend_Locale object
	 */
	protected $_locale;

	/**
	 * The Alphabet means english alphabet.
	 *
	 * @var boolean
	 */
	protected static $_meansEnglishAlphabet;

	/**
	 * Sets default option values for this instance
	 *
	 * @param  boolean $allowWhiteSpace
	 * @return void
	 */
	public function __construct($allowWhiteSpace = false)
	{
		$this->allowWhiteSpace = (boolean) $allowWhiteSpace;
		if (null === self::$_unicodeEnabled) {
			self::$_unicodeEnabled = (@preg_match('/\pL/u', 'a')) ? true : false;
		}

		if (null === self::$_meansEnglishAlphabet) {
			$this->_locale = new Zend_Locale('auto');
			self::$_meansEnglishAlphabet = in_array($this->_locale->getLanguage(),
			array('ja', 'ko', 'zh')
			);
		}

	}

	/**
	 * Returns the allowWhiteSpace option
	 *
	 * @return boolean
	 */
	public function getAllowWhiteSpace()
	{
		return $this->allowWhiteSpace;
	}

	/**
	 * Sets the allowWhiteSpace option
	 *
	 * @param boolean $allowWhiteSpace
	 * @return Zend_Filter_Alnum Provides a fluent interface
	 */
	public function setAllowWhiteSpace($allowWhiteSpace)
	{
		$this->allowWhiteSpace = (boolean) $allowWhiteSpace;
		return $this;
	}

	/**
	 * Defined by Zend_Filter_Interface
	 *
	 * Returns the string $value, removing all but alphabetic and digit characters
	 *
	 * @param  string $value
	 * @return string
	 */
	public function filter($value)
	{
		$whiteSpace = $this->allowWhiteSpace ? '\s' : '';
		if (!self::$_unicodeEnabled) {
			// POSIX named classes are not supported, use alternative a-zA-Z0-9 match
			$pattern = '/[^a-zA-Z0-9' . $whiteSpace . ']/';
		} else if (self::$_meansEnglishAlphabet) {
			//The Alphabet means english alphabet.
			$pattern = '/[^a-zA-Z0-9'  . $whiteSpace . ']/u';
		} else {
			//The Alphabet means each language's alphabet.
			$pattern = '/[^\p{L}\p{N}' . $whiteSpace . ']/u';
		}

		return preg_replace($pattern, '', (string) $value);
	}
}
